Blasting machine



y 1952 R. a HUYETT ETAL 2,604,734

' BLASTING MACHINE Filed Jan. 5, 1950 4 Sheets-Sheet 1 BY 5 W" July 29, 1952 R. B. HUYETT ET AL BLASTING MACHINE 4 Sheets-Shet 2 Filed Jan. 5. 1950 I N VEN TOR5 fPOsEl-PT s. HUYE 777 M 5 W W M R a G July 29, 1952 R. B. HUYETT ET AL BLASTING MACHINE 4 Sheets-Sheet 3 Filed Jan. 5, 1950 5Q v K k r WW Mia) wuflgkvfi .E- r 11 J a E L IL L w -1! w 1% 440E I J, l a w a I m .3 v m. E WW huh hm WW m wwV A NQSQDPR lm pug D 1 t July 29, 1952 R. B. HUYETT ET AL BLASTING MACHINE 4 Sheets-Sheet 4 Filed Jan. 5 1950 I'NVENTOR5 M5E/PT-BJVUYEW; GEORGE [4. @WELL Patented July 29, 1952 BLASTIN G MACHINE Robert B. Huyett and George W. Powell, Hagerstown, Md., assignors to Pangborn Corporation, Hagerstown, Md a corporation of Maryland Application January 5, 1950, Serial N 0. 136,902

7 Claims. (CI. 5114) This invention relates to work blasting machines and aims generally to improve the same. In particular, it aims to provide an improved cabinet-type blasting machine for handling and treating cylindrical, or flanged cylindrical,- objects to be blasted. Examples of such articles are drums, cylindrical shaft sections, end-flanged rear axle shafts, and the like.

In the treating of short cylindrical objects, such for example as round shafts, tubes, drums, or pipes of steel, iron, wood or other relatively rigid material, with projected treating material, considerable difficulty is experienced in obtaining uniform treatment of the work. An important object of the present invention is to provide means for supporting, advancing and rotating such articles so as to obtain maximum uniformity in treatment thereof. Other objects are to improve the cheapness and efficiency of such blasting procedure, to provide arrangements for advancing such articles substantially longitudinally at a predetermined rate while rotating them at a predetermined rate, and to provide arrangements for so doing without obscuring theends of the articles. Still further objects will appear from the following detailed description of preferred embodiments of the invention, including the provision of improved details of construction and arrangements of parts contributing to the attainment of various of the aforesaid objects.

The invention itself consists in the new and useful features and combinations herein described and particularly pointed out in the appended claims.

In the accompanying more or less diagrammatic drawings of exemplary embodiments of the invention:

Figs. 1 and 2 are side and end elevations of a blasting machine including one form of the invention.

Fig. 3 is a plan view thereof.

Figs. 4 to 6 are plan, elevation, and end views of the work-conveying means thereof.

Figs. 7 to 9 are diagrams explaining the operation of the work conveyor.

Figs. 10, 11 and 12 are plan, elevation, and end views of a second embodiment of work-conveying means.

Fig. 13 is a diagram of a third embodiment.

General arrangement In the illustrative form of Figs. 1 to 3 the blasting machine shown comprises a housing I defining a blasting chamber 2 shown as extending longitudinally of the machine from its entrance end 3 to its discharge end 4. e

Blasting means 5, of any form suitable to the operation to be performed, is arranged todischarge into the chamber 2. For shot and "grit peening and blasting operations the blasting means 5 may be of the airless centrifugal wheel type, exemplified. for example in Rosenberger and Keefer Patent No. 2,352,588, issued June 27, 1944. Such machines, as indicated in Fig. 1, project the blastant material in a fan-shaped stream having an intensity distribution or'pattern of the form diagrammatically indicated at 6. In the arrangement of Figs. 1 to 3 two such wheels 5 are employed, and these machines are preferably ar-' ranged to rotate in opposite directions in sub stantially the same plane, to project their fanshaped streams from the center of the blasting chamber 2 toward the ends 3 and 4, respectively, and along the work-path extending through the blasting chamber.

As is usual in shot and grit blasting, the machine of Figs. 1 to 3 comprises, below the workpath, a hopper I provided with a screen 8 and a longitudinally arranged screw conveyor 9 for delivering the spent blastant to the foot of a blast-- ant elevator ill (of any conventional form), a chain-bucket elevator bein the form usually employed. The elevator ID, at its upper end, delivers to chute means II by which the abrasive or other blastant is returned through classifying and separating means 12 to supply hoppers l3, from which the blastant is supplied through feed conduits I4 to the blasting means 5. Suit are provided for the various conveying and projecting means, herein exemplified by the'motor and belt drivel! for the screw'conveyor 9 and elevator Hi; the motor and belt drives I8, for the work-handling rolls hereafter described; and the motor and belt drives I9 for the centrifugal wheels 5. Suitable ventilating arrangements 20 and access ladders and platforms 2| are also usually provided. 7

Work-handling means Referring now to Figs. 1 to 6. as is there shown the work-conveying means of thepreferred embodiment comprises a pair of rolls 25, parallel in plan view (Figs. 3 and 4) but oppositely inclined in side elevation (Figs. 1 and 5). These rolls-25,

in the form shown, extend lengthwise or longituj din'ally through the blasting chamber 2, in mutually spaced relation, with the winding, worksupporting notch between them generally aligned with the plane of the fan-shaped blast streams 6 (Fig. l). The rolls 25 are supported in suitable bearings 26 at their ends (Figs. 1 and 4), and as shown in Fig. 6 are rotated in the same sense so that cylindrical work-pieces -21 resting in the notch between rolls 25 are rotated in the opposite sense and advanced lengthwise along the notch at a predetermined rate.

The rate of advance of the work-pieces 21 along the rolls 25 is determined by the angle at which the cylindrical object contacts the rollsurfaces when the conveying rolls are caused to revolve and the cylindrical object or work is lying in the notch or valley between the two, adjacent rolls.

The diameter of the conveying rolls 25 may be of any convenient or practicable size. The revolving speed may be of any practical speed dependent upon the desired lengthwise. advance, of the work per unit-of time.

The diameter of the cylindrical object or work 21 may be of any practical size within the limitations of the roll spacing and other physical relationships of the particular machine in which the invention is embodied. The roll spacing may be varied, as may the angle of relative inclination of the rolls 25, by suitable. adjustment of the roll bearings 26, to enable a given machine to accommodate a series of small, medium or large diameters and to eifect various predetermined rates of advance of the articles. This type of conveyor may therefore be flexible in its use for various kinds of cylindrical objects.

For rotating and conveying cylindrical objects which are relatively short, say 3-inchlengths up to 36- to 48-inch lengths, a small angular relationship, say one givingfrom 1 tot or angularity to the work, is preferred. The sizes and lengths of work .handleable in this manner may be varied, at will, provided the size of the machine A=1rD tan B in which =rate of advance in feet per revolution 1r=the constant pi-"=3.14l6

D=the diameter of the work B=the angle at which thecylindrical object contacts the roll surfaces.

In other words, referring to-the diagram of Fig. 4, 1rDbeing the distance laid out as circumference of-straight object and the angle of'work travel B being as shown, it will be seen that the distance 1D corresponds to the adjacent side, and the distance-FD tan B.to the opposite side of the .right triangle constructed onthe angle, B.

Applyingthis formula, it will be seen thatwhen the angle is 3 and the work diameter 2 inches, the tangent of the angle is .0524, the circumference of the work is 6.2832 inches, and the advance per revolution of the workis 0.329 inch.

By varying the conveying rollR. P. M., the speed of rotation andspeed of advance of the work may beconcurrently varied.

Figs. 5, 7.8 and 9 show fourarrangements of the 'rollswhich may be employed. In the preferred arrangement (Fig. the rolls, as shown 4 in Figs. 1 to 5, are oriented at opposite angles to the horizontal, and cross the horizontal line at any point between their end mountings. In the arrangement of Fig. 7, the rolls are still arranged at opposite angles to the horizontal, but do not cross the horizontal between their end mountings. .As shown in Figs. 8- and 9, one or the other of the rolls may be mounted horizontally, the companion roll only being inclined to the horizontal. Each of these arrangements produces a winding valley or notch between the roll surfaces afiording concurrent rotation and lengthwise feeding of the work.

I The work-pieces may be delivered to and from the work conveyor 25 in any desired way, and the machine is particularly flexible in this regard. Feed and delivery over the ends of the rolls through hanging rubber curtains or other abrasive-trapping means is feasible when the plant layout renders straight linear handling desirable. And as shown in Figs. 1 to 3, when nonlinear arrangements are desired, the work may be rolled into the machine transversely as shown at 21a, Fig. 3, as down an inclined plane 30 (Fig. 2) and at the delivery end 4 of the machine the work may be deflected or turned through a right angle, as by a curved guide wall 3| (Fig. 3) and may then slide outwardly transverse of the machine axis, as down an inclined plane or chute 32 (Fig. 2). Where little treatment of the ends of the work-pieces is desired, they may be fed in close formation. If fed in open formation substantially uniform spacing of the articles is maintained and the ends of the articles are not obscured and are exposed to the blastant.

As is shown in Figs. 1 and 2, confining walls or baffles 33, which may be rubber-covered, may be disposed at either side of the blast stream to assure delivery of only a narrow stream of blastant against the upper side of the work passing along the notch between the rolls. Where the diameter of the work permits, the rolls may be spaced apart a distance greater than the width of the blast stream. In either case the rolls themselves are aiforded maximum protection against the action of the abrading medium, since direct impact thereof is substantially limited to impingement against the work, and when no work is present the blastant, or a substantial part of it, may pass downwardly between the rolls and'impinge upon them, if atv all, only at a narrow angle of minimum effectiveness for abrading them. In addition, the rolls, or desired portions of them, may be rubber-surfaced or otherwise formed to resist the action of the blasting medium. Scrap material 34 or the like may be positioned below the rolls, as on screen 8, if desired, to receive the impact of blasting abrasive.

The form shown in Figs. 1 to 6 employs rolls spaced apart and is intended to handle work laterally rollable on plain cylindrical surfaces. The invention is not limited to this particular arrangement however. As exemplifying this fact, there is shown in Figs. 10. to 12 a second embodiment adapted to handle either straight cylindrical objects or flanged cylindrical objects.

In this form the rolls 250. are in the form of screw members, which may be spaced apart as in Figs. 1 to 6, or may be interlapped as shown in Figs. 10 and 12. Here again, the rolls are so supported, as by bearings 26, that their axes are relatively inclined to the horizontal plane so that straight work Zla supported in the notch or valley between the outer surfaces of the rolls is advanced by the tangent relationship, as before (see Fig.

10). With this construction the shortness of the cylindrical work that can be handled is limited to not less than about two pitch lengths; i. e., when the pitch of the spiral is, say, inches, to insure against clogging a minimum work length of to 11 inches should be handled.

With this construction, however, flanged work, exemplified at Zl'b, Figs. 11 and 12, may also be handled, the flange or flanges descending between the spiral vanes of the screws a. This form of machine is particularly suited for handling cylindrical work having a disc-like flange on one end, such as an automobile rear axle shaft 2Tb. In this case the rate of advance of the work is limited and determined by the pitch of the screw acting against the flange, as is evident from Figs. 11 and 12.

For purposes of simplicity, a single pair of rolls will usually be employed, but three or more rolls may be used to carry a plurality of rows of articles through the blasting chamber.

When employing three rolls, as shown in the elevation diagram (Fig. 13), the center roll is preferably arranged horizontally, with the first and third rolls inclined upwardly and downwardly, respectivel relative thereto.

While the present invention cooperates particularly well with airless-type centrifugal blasting machines, which project relatively narrow fan-shaped patterns of treating material, with less advantage compressed air nozzles or other forms of treating-material projectors may be employed, singly or in multiple. The treatment practiced may be a peening or cleaning treatment.

or a surface-finishing treatment removing or adding a coating to the work-pieces. In its broader aspects, features of the invention may be applied to machines for treating work with rust inhibiting solutions or other spray cabinet-coating materials, especially where the treatment is to be practiced over the entire exposed circumference and length of a generally transversely rollable object. The embodiments shown are therefore to be regarded as illustrative and not restrictive of the invention, the scope of which is defined in the appended claims, and all modifications and changes which come within the meaning and range of equivalency of the claims are intended to be included therein.

We claim for our invention:

1. In a blasting machine for blast treating relatively short laterally rollable articles, a blasting chamber, a pair of work supporting rolls extending longitudinally in said chamber, means for rotating said rolls in the same direction, said rolls lying substantially parallel in plan view but at a relative inclination in elevational view and thus presenting a winding notch or valley between them for supporting the relatively short laterally rollable articles and causing them to advance lengthwise of said notch as they are rotated transversely therein, means for projecting blastant downwardly in said chamber in a fanwise stream directed longitudinally of said notch and against the upper sides of articles being rolled and advanced therein, and. baffle means for confining the stream of blastant for direct impingement thereof only against the top surfaces of said articles.

2. In a blasting machine for blast treating relatively short laterally rollable articles, a blasting chamber, a pair of work supporting rolls extending longitudinally in said chamber, means for rotating said rolls in the same direction, said rolls lying substantially parallel in plan view but means for projecting blastant against articles being rolled and advanced in said notch.

3. In a blasting machine for blast treating I relatively short laterally rollable articles, a blasting chamber, a pair of work supporting rolls extending longitudinally in said chamber, means for'rotating said rolls in the same direction, said rolls lying substantially parallel in plan view but at a relative inclination in elevational view and thus presenting a winding notch or valley between them for supporting the relatively short laterally rollable articles and causing them to advance lengthwise of said notch as they are rotated transversely therein, inclined plane means for rolling the articles laterally into the input end of the notch, guide means for displacing the articles laterally from the delivery end of the notch, and means for projecting blastant against articles being rolled and advanced in said notch.

4. In a blasting machine for blast treating relatively short laterally rollable articles, a blasting chamber, a pair of work supporting rolls extending longitudinally in said chamber, means for rotating said rolls in the same direction, said rolls lying substantially parallel in plan view but at a relative inclination in elevational view and thus presenting a winding notch or valley between them for supporting the relatively short laterally rollable articles and causing them to advance lengthwise of said notch as they are rotated transversely therein, means for rolling the article laterally into the input end of the notch, guide means extending across said notch for displacing the articles therefrom and turning them through substantially during such displacement, and means for projecting blastant against articles being rolled and advanced in said notch.

5. In a blasting machine for blast treating relatively short laterally rollable articles, a blasting chamber, a pair of work supporting rolls extending longitudinally in said chamber, means for rotating said rolls in the same direction, said rolls lying substantially parallel in plan view but at a relative inclination in elevational view and thus presenting a winding notch or valley between them for supporting the relatively short laterally rollable articles and causing them to advance lengthwise of said notch as they are rotated transversely therein, means for rolling the article laterally into the input end of the notch, curved guide means extending across said notch for displacing the articles therefrom and turning them through substantially 90 during such displacement, inclined plane means for sliding said turned articles from the machine, and means for projecting blastant against articles being rolled and advanced in said notch.

6. In a blasting machine for blast treating a,

inclination in elevational view and thus presenting, a winding notch or valley between. themv for supporting the relatively short laterally rollable articlesand causing them to advance lengthwise of said notch as they are rotated transversely therein, the pitch of said screwlike rolls being such that the rate of advance of flanged rollable articles received thereon is limited and determined thereby, and means for projecting blastant against artic1es being rolled and advanced in said notch.

7. In a blasting machine for blast-treating elongated laterally rollable articles, a fixed foundation structure for supporting the machine, a blasting chamber positioned over said foundation structure, a pair of elongated cylindrical worksupporting rollers, fixed journal elements held on said foundation structure and fixedly supporting said rollers for rotation about their axes with the rollers substantially parallel in plan view but at a relative inclination of not more than about 4 in elevational view, and with the rollers extending in spaced relation across said chamber to thereby present an elongated winding notch between them for supporting the rollable articles; means-for rotating said rollers in the same direction about their respective longitudinal axes and thereby causing said rollable articles. freely supported in the notch, to rotate and advance longitudinally in said notch while rotating; blasting means in said blast chamber and positioned adjacent said rollers to uniformly blast surface portions of said articles presented to the blasting means during their travel along the notch; and supply means connected to supply blastant material to said blasting means.

ROBERT B. HUYE'I'I.

GEORGE W. POWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,568,958 Carter Jan. 12, 1926 1,804,422 Koch May 12, 1931 1,928,339 Mulvaney Sept. 26, 1933 1,987,850 Heim Jan. 15, 1935 2,154,843 Hammell Apr. 18, 1939 

